Calculating device



Dec. 5, 1950 Filed June 28, 1948 E. W. HEERICH CALCULATING DEVICE Working 77MB S tart 5M6 3 Sheets-Sheet l INVENTOR Dec. 5, 1950 E. w. HEERICH CALCULATING DEVICE 3 Sheets-Sheet 2 Filed June 28, 1948 j magi. b blo o b b o a x5532. odaaada ENTOR Patented Dec. 5, 1950 UNITED STATES PATENT OFFICE CALCULATING DEVICE Edgar W. Heerich, Westfield, N. J.

Application June 28, 1948, Serial No. 35,568

4 Claims. 1

This invention pertains to calculating devices and more particularly to calculating devices of the slide rule type.

The problem of keeping time records for pay and accounting purposes has always been a tedious and time consuming job entailing considerable expense. It involves translating starting and finishing times into elapsed time in the form of hours and fractional or decimal portions of an hour. This becomes increasingly bothersome when the periods being recorded begin and end at irregular times as when an employee starts late or quits early, or changes jobs at irregular times during the day in cases where the time spent on each job must be recorded. Aside from the time consumed in calculating elapsed time mentally or by other methods now in use, it is a frequent source of error.

An object of this invention is to provide a calculating device of the slide rule type that will indicate the correct elapsed time b one setting when the starting time and finishing time are known.

Another object is to provide such a device that will account for a lost time period, such as a lunch period, between the starting and. finishing times.

Another object is to provide a device of the type described that will read directly the elapsed time for less than twelve hours and for elapsed times between twelve and twenty-four hours.

Another object is to provide a device of the type described that is compact in size and convenient to read, and in which the elapsed time always appears in an upright position on the same face the scales are set from. I

Another object is to provide a device of the type described in which it is impossible to read an incorrect answer because of improper assembly of the parts.

Other objects, features and advantages of the invention will appear or be pointed out as the description proceeds.

In the drawings forming a part hereof, and in which like reference characters denote correslide setting.

Fig. 5 illustrates the reverse side of the device of Fig. 3.

Referring now to Fig. 1, a body portion 10 is suitably constructed to receive a slide H by any of the Well known forms of slide rule construction. The body portion in this case comprises two face plates separated by spacers. (Fig. 2.) On the face of the body In is a scale A representing twelve hours and subdivided into any convenient number of parts, such as the fifteen minute divisions illustrated. This is based on our conventional system of telling time by 12 hour cycles. Adjacent to scale A is a window I2. Two other windows 13 and i4, near the top and bottom respectivel are provided in the face of the body I9.

The slide II bears three scales, one exactly like scale A and hereafter referred to as scale B, which is properly aligned to appear in window i2 of the body. The two other scales on the slide, denoted by letters C and D, represent the elapsed time to be determined and are properly aligned so one number from each scale appears in window 13 or window i4, depending on the If scales A and B represent12 hours, as illustrated, scales C and D also represent 12 hours. If scale A runs from 12 oclock to 12 oclock, scale B also runs from 12 oclock to 12 oclock, scale C from 0 to 12 hours, and scale D from 12 to 24 hours. Scales C and D, are preferably made to read in hours and fractional or decimal parts of an hour while scales A and B preferably read in hours and minutes.

In order to determine the time elapsed between some time on scale A and some other time on scale B, it is only necessary to set the slide I I to a position in which the finishing time on scale B is opposite the starting time on scale A and the elapsed time will appear on scale C in window [3 or window 14' if less than 12 hours, or on scale D in window [3 or window [4 if between 12 and 24 hours. For example, referring to Fig. 1, should it be necessary to find the elapsed time between 5:45 and 8:15, set the slide so 8:15 on scale B is opposite 5:45 on scale A and find the elapsed time, 2%; hours, on scale C in window iii. For an around the clock shift the elapsed time of 14 hours appears on scale D in window 53.

It should be noted that the scales need notbe laid out to read in order from 12 to 12, but might start and end at any other convenient hour without departing from this invention. It is only necessary that scales C and D be properly correlated to indicate the correct elapsed time. While the construction thus far described is scales.

which the-starting-time-scale is dividedyis illussatisfactory if the work period is uninterrupted from start to finish, it is usually necessary to account for a lunch period or other lost time. To provide for this an outer slide I is added. This slide may be made of transparent material as illustrated or may be opaque with appropriate Windows to expose the scales as necessary. This slide I5 bears scale L which represents the time out period (lost time), and when properly used with scales A and B-perinits the net time worked to appeafinwindow [3 or IE.

Its proper use is as follows. Select the starting time on scale A and adjust the position of the outer slide to align the startingtime-and the figure on scale L representingthe length of the lunch period. Move the inner-slide -l i 'uhtil the finish time on scale B is aligned: with the figure 0 on scale L. The net time worked now appears in window l3 or M. Guide liiiesabove and below figure 0 of scan L assist in the correct and'rapid setting of slide 1 I.

For example let the starting time be lz3ili the lunch intermission- 30 1nin.,-- and the-"finishing timeoe 8:15. The slides -areset asi-llustrated' in Fig. l and'the'net elapsed time-of 3-; /4- hours :appears in" window l3.

The form of the invention illustrated-in Fig. 1

tervals instead 'of -15-minute intervals -as shown,

the slide rule -oi--Fig. 1--becomes cumbersome,

since'eachwhour 'now' is-represented- .by 12 subdivisions instead ofifour. To keep the scales large enough to be easy to use, and atthe same time to keep the whole assembly from becoming unwieldy, the modification-showninFigs;-3 and 5 has been iound verysatisiactcry. Instead of having "all twelve hours on one starting time scale (scale A, Fig.4) this scale may be divided into two-or more parts when -properly=combined withappropriate finishing-and elapsed time The preferred form of the invention in trated in Figs. 3-; 4 "and 5.- Inthis form thestarting time scale represents six hours and there are two matching finishing-scales "each representing six hours which when taken together givea full twelve hours of finishing time,- thus: providing for every possible finishing time. Foreach finishing time scale there is a scale to read elapsed-time less than 12- hours and'one toread elapsed time between 12 and 24hours. Forthe other six hours of possible startin times, a similar arrangement of scales-is provided on-the reverse sideof the rule.

Referring to Figs. 3, 4- and 5, the-structure shown comprises a front bod portiona pair of separators *2 I a -back body portion 22'; and a slide 23. The separators are securely attached to bothbody portions. -Ap-propriate windows are provided in the bod portions 'for matching the scales and reading elapsed time n v For example, scale-E (Fig. 3) denotes 6 hours of starting time in 5imi-nute intervals. 1 Oneither side of this scale are windows} denoted--24 and 25, through whichscales Land J of the slide 23 arevisible. Scale E denotes starting:- time-and scales I and J denote finishing times.- Scales I' and J each denote 6 hours-in-five-minute intervals, the same inthat respect as scaleE, but

' scale 1, runs from 6 oclock-to '12 o'clock and scale J from '12 oclockto 6 o--clock. Thereforepusing scales E and I or J, every possible finishing time can be ali ned with any starting time between 12 oclock and 6 oclock. For any selected starting time on scale E and finishing time on scale I, the elapsed time appears on scale G or H. These are also 6 hour scales in 5 minute divisions, but read directly in hours and decimal parts of an hour. Scale G goes from 0 to 6 hours, and scale H from 6 to 12 hours giving the full number of possible answers for less than 12 hours, elapsed time; The scales "of course are properly aligned so the correct elapsed time becomes visible through window 26 or 27 depending on the K or L in window 28 or 29. An additional pair of 'scal'es may be added on each side of the E scale to read elapsed times around the clock, that is; between 12 and 24 hours, or just two need be used'iscales F and M) if the correct windows are used to read the answers. By the same reasoning scales G and K and scales H and L could be combined, but that has been found to be confusing.

Fig. 5 illustrates the other side of the slider'ule of Fig. 3 and is used for starting'times between 6 and 12 oclock. It is based-on the same principle as described above for Fig. 3- and is shown with the slide at such a setting that it projects from the bottom of the body.

- By'combining the scales of- Figs. 3 and 5 into one two sided device, it becomes ver handy and. compact. In order to prevent the slide from being removed and replaced backwards, resulting in incorrect answers, the scales on opposite sides may be mis-alig-ned by half a column; so they will not show through the: windowsin'the body if incorrectly assembled. In'Figs'. 3; 4. and-5;-a transparent slide 30 carries auxiliary scales to allow for lost time in e'x'a'ctIy the-same way as described heretofore in connection with Fig. 1.

Other scales may be substituted for theela'psed time scales shown for giving 'answ'ers' above 24 hours, or for reading time :costs directl provided a different scale is used for each hourly rate.

Various changes and modifications can' be made, and some features of the invention can be used without others, without-departing from the invention as defined-in the claims.

I claim:

1-. A calculating device of the slide rule type having a fixed part, a second part movablewith respect to the fixed part, a-firstscale on the fixed part representing six hours, a secondscale on the movable part representing six hours of a twelve hour period,- a third scale on the movable part representing the remaining six hours of said twelve hour period, means fonaligning any given point on said'first scale with any given point on said second scale or with any given point on said third scale, a fourth scale on'the movable part, an index on the fixed part, said'index indicating a point on said fourth scale that represents the elapsed time between any point on said first scale and'an aligned point on said second scale, a fifth scale on the movable'part, and a second indexon the fixed 'p'art, said "second index indicating a point on said fifth scale that represents the elapsed time between any point on said first scaleand an aligned point on said third scale.

- 2. A calculating device-according to claim 1 having a similar set of scales and :indices on its reverse side in which the firstscale on the-reverse side represents the remaining six hours of 1 a 7 5 twelve hour period from that represented by the first scale in claim 1.

3. A calculating device according to claim 1 having a similar set of scales and indices on its reverse side but having the first scale on the reverse side represent the remaining six hours of a twelve hour period from that represented by the first scale in claim 1, and having the scales on the opposite sides of the movable part in offset relation to prevent improper alignment of the scales of the movable part and the scales and indices of the fixed part when the movable part is improperly assembled in the fixed part.

4. A calculating device according to claim 1 having an auxiliary slide mounted to move with 15 respect to the fixed part and having an auxiliary time scale on said auxiliary slide so positioned that any point on said auxiliary time scale can REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 944,218 Sommer Dec. 21, 1909 FOREIGN PATENTS Number Country Date 491,676 France Feb. 12, 1919 

